Plugins load from packages is missing regex check

[GeckoEidechse]

Ugh, I just realised another issue with this.

This doesn't do the regex check that the modmanager.cpp code does to ensure that package is installed correctly.

NorthstarLauncher/NorthstarDLL/mods/modmanager.cpp

Lines 622 to 623 in 82bff57

	// Set up regex for `AUTHOR-MOD-VERSION` pattern
	std::regex pattern(R"(.*\\([a-zA-Z0-9_]+)-([a-zA-Z0-9_]+)-(\d+\.\d+\.\d+))");

Also I'm pretty sure it still loads plugins recursively which we shouldn't need to do anymore. The only reason we added recursive load was to have a plugin -> Thunderstore-package mapping with the old plugin system, i.e. #460 which can also be reverted now.

Originally posted by @GeckoEidechse in #513 (comment)